GETTING READY
1. Shell and clean prawns.
2. Reserve their heads and shells.
3. Slice prawns into 3-4 pieces, season with salt and set aside.
4. Wash prawn heads and shells well, mash them lightly and add to stock.

MAKING
5. In a pan place stock over high heat.
6. Bring to a boil, lower heat and simmer for about 10 minutes.
7. Return the stock to the pan after straining the stock, discarding prawn heads and shells.
8. Bring stock to a boil over high heat.
9. Add together, noodles, spring onions, bean sprouts, ginger and garlic.
10.When the noodles are almost tender, add the prawns, lower heat and simmer till prawns and noodles are just cooked.
11. Take pan off the heat and stir in pepper, Thai sweet chilli sauce, fish sauce and lime juice for taste and adjust seasoning accordingly.